Danskammer Unit 4 March 2012

EPA analysis of cost-effectiveness and visibility improvements based on Dynegy BART analysis

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SO2 Lime Based Spray Dryer FGD with Baghouse emission rate

lb/hr tons/yr mmBTU/hr lb/mmBTU

from Dynegy spreadsheet-------- 234.9 1028.9 2512 0.094

 from Dynegy spreadsheet--------annualized costs $20,371,635

maximum 8th

dv dv

Class I Areas improvement $/dv improvement

Lye Brook Wilderness Area, VT 0.338 $60,271,109 0.677

Acadia National Park, ME 0.701 $29,060,820 0.337

Brigantine Wilderness Area, NJ 1.423 $14,315,977 0.416

Presidential Range Wilderness Area, NH 0.843 $24,165,641 0.278

Great Gulf Wilderness Area, NH 0.756 $26,946,607 0.242

Dolly Sods Wilderness Area, WV 0.358 $56,904,008 0.116

Otter Creek Wilderness Area, WV 0.33 $61,732,227 0.108

Total 4.749 $4,289,668 2.174

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SO2 0.50 lb SO2/mmBTU proposed BART limit emission rate

lb/hr tons/yr mmBTU/hr lb/mmBTU

from Dynegy spreadsheet-------- 1256 5501.3 2512 0.500

 from Dynegy spreadsheet--------annualized costs $11,108,177

maximum 8th

dv dv

Class I Areas improvement $/dv improvement

Lye Brook Wilderness Area, VT 0.511 $21,738,115 0.245

Acadia National Park, ME 0.301 $36,904,243 0.169

Brigantine Wilderness Area, NJ 0.667 $16,653,939 0.22

Presidential Range Wilderness Area, NH 0.462 $24,043,673 0.119

Great Gulf Wilderness Area, NH 0.416 $26,702,349 0.135

Dolly Sods Wilderness Area, WV 0.209 $53,149,172 0.067

Otter Creek Wilderness Area, WV 0.193 $57,555,321 0.06

Total 2.759 $4,026,161 1.015

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SO2 Gas Cofiring at 60% emission rate

lb/hr tons/yr mmBTU/hr lb/mmBTU

from Dynegy spreadsheet-------- 1075.8 4712.0 2512 0.428

 from Dynegy spreadsheet--------annualized costs $15,315,564
maximum 8th

dv dv

Class I Areas improvement $/dv improvement

Lye Brook Wilderness Area, VT 1.102 $13,897,971 0.42

Acadia National Park, ME 0.506 $30,267,913 0.239

Brigantine Wilderness Area, NJ 0.985 $15,548,796 0.307

Presidential Range Wilderness Area, NH 0.646 $23,708,303 0.206

Great Gulf Wilderness Area, NH 0.577 $26,543,438 0.192

Dolly Sods Wilderness Area, WV 0.287 $53,364,334 0.083

Otter Creek Wilderness Area, WV 0.261 $58,680,322 0.075

Total 4.364 $3,509,524 1.522

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Nox 0.12 lb NOx/mmBTU proposed BART limit (same as gas cofiring 100% @ 0.12 lb/mmBTU)

emission rate

lb/hr tons/yr mmBTU/hr lb/mmBTU

from Dynegy spreadsheet-------- 301.4 1320.1 2512 0.120

 from Dynegy spreadsheet--------annualized costs $20,094,818

maximum 8th

dv dv

Class I Areas improvement $/dv improvement

Lye Brook Wilderness Area, VT 0.829 $24,239,829 0.23

Acadia National Park, ME 0.300 $66,982,727 0.116

Brigantine Wilderness Area, NJ 0.221 $90,926,778 0.122

Presidential Range Wilderness Area, NH 0.227 $88,523,427 0.029

Great Gulf Wilderness Area, NH 0.200 $100,474,090 0.063

Dolly Sods Wilderness Area, WV 0.090 $223,275,756 0.004

Otter Creek Wilderness Area, WV 0.076 $264,405,500 0.005

Total 1.943 $10,342,161 0.569

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Nox FGR

emission rate

lb/hr tons/yr mmBTU/hr lb/mmBTU

from Dynegy spreadsheet-------- 970.6 4251.2 2512 0.386

 from Dynegy spreadsheet--------annualized costs $348,655

maximum 8th

dv dv

Class I Areas improvement $/dv improvement

Lye Brook Wilderness Area, VT 0.091 $3,831,374 0.034

Acadia National Park, ME 0.033 $10,565,303 0.014

Brigantine Wilderness Area, NJ 0.025 $13,946,200 0.019

Presidential Range Wilderness Area, NH 0.026 $13,409,808 0.015
Great Gulf Wilderness Area, NH 0.022 $15,847,955 0.002

Dolly Sods Wilderness Area, WV 0.010 $34,865,500 0

Otter Creek Wilderness Area, WV 0.008 $43,581,875 0

Total 0.215 $1,621,651 0.084

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Nox FGR + SCR

emission rate

lb/hr tons/yr mmBTU/hr lb/mmBTU

from Dynegy spreadsheet-------- 962.7 4216.6 2512 0.383

 from Dynegy spreadsheet--------annualized costs $8,458,077

maximum 8th

dv dv

Class I Areas improvement $/dv improvement

Lye Brook Wilderness Area, VT 1.062 $7,964,291 0.243

Acadia National Park, ME 0.383 $22,083,752 0.146

Brigantine Wilderness Area, NJ 0.281 $30,099,918 0.136

Presidential Range Wilderness Area, NH 0.288 $29,368,323 0.033

Great Gulf Wilderness Area, NH 0.254 $33,299,516 0.08

Dolly Sods Wilderness Area, WV 0.113 $74,850,239 0.005

Otter Creek Wilderness Area, WV 0.096 $88,104,969 0.008

Total 2.477 $3,414,646 0.651

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Nox Hybrid SNCR/SCR

emission rate

lb/hr tons/yr mmBTU/hr lb/mmBTU

from Dynegy spreadsheet-------- 422 1848.4 2512 0.168

 from Dynegy spreadsheet--------annualized costs $9,296,984

maximum 8th

dv dv

Class I Areas improvement $/dv improvement

Lye Brook Wilderness Area, VT 0.942 $9,869,410 0.273

Acadia National Park, ME 0.323 $28,783,232 0.126

Brigantine Wilderness Area, NJ 0.344 $27,026,116 0.138

Presidential Range Wilderness Area, NH 0.242 $38,417,289 0.053

Great Gulf Wilderness Area, NH 0.213 $43,647,812 0.078

Dolly Sods Wilderness Area, WV 0.097 $95,845,196 0.012

Otter Creek Wilderness Area, WV 0.083 $112,011,855 0.009

Total 2.244 $4,143,041 0.689

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Nox Gas Cofiring at 100% @ 0.08 lb/mmBTU
emission rate

lb/hr tons/yr mmBTU/hr lb/mmBTU

from Dynegy spreadsheet-------- 201 880.4 2512 0.080

 from Dynegy spreadsheet--------annualized costs $25,525,939

maximum 8th

dv dv

Class I Areas improvement $/dv improvement

Lye Brook Wilderness Area, VT 2.430 $10,504,502 0.888

Acadia National Park, ME 1.026 $24,879,083 0.448

Brigantine Wilderness Area, NJ 1.815 $14,063,878 0.551

Presidential Range Wilderness Area, NH 1.219 $20,940,065 0.391

Great Gulf Wilderness Area, NH 1.085 $23,526,211 0.349

Dolly Sods Wilderness Area, WV 0.527 $48,436,317 0.139

Otter Creek Wilderness Area, WV 0.475 $53,738,819 0.13

Total 8.577 $2,976,092 2.896
======================

$/dv

$30,091,041

$60,449,955

$48,970,276

$73,279,263

$84,180,310

$175,617,543

$188,626,250

$9,370,577

======================

$/dv

$45,339,498

$65,728,858

$50,491,714

$93,346,025

$82,282,793

$165,793,687

$185,136,283

$10,944,017

======================
$/dv

$36,465,629

$64,081,858

$49,887,831

$74,347,398

$79,768,563

$184,524,867

$204,207,520

$10,062,788

======================

12 lb/mmBTU)

$/dv

$87,368,774

$173,231,190

$164,711,623

$692,924,759

$318,965,365

$5,023,704,500

$4,018,963,600

$35,316,025

======================

$/dv

$10,254,559

$24,903,929

$18,350,263

$23,243,667
$174,327,500

$4,150,655

======================

$/dv

$34,806,901

$57,932,034

$62,191,743

$256,305,364

$105,725,963

$1,691,615,400

$1,057,259,625

$12,992,438

======================

$/dv

$34,054,886

$73,785,587

$67,369,449

$175,414,792

$119,192,103

$774,748,667

$1,032,998,222

$13,493,446

======================
$/dv

$28,745,427

$56,977,542

$46,326,568

$65,283,731

$73,140,226

$183,639,849

$196,353,377

$8,814,205